Devices and methods for treating a lung

ABSTRACT

Methods and devices for treating a lung are disclosed. The method may include deploying a catheter into an airway of the lung, and discharging a media into the airway through the catheter. The media may be configured to increase elasticity of lung tissue in the vicinity of the airway or occlude the airway.

CROSS-REFERENCE TO RELATED APPLICATION

This patent application claims benefit of priority under 35 U.S.C. §119to U.S. Provisional Patent Application No. 61/968,915, filed Mar. 21,2014, the entirety of which is incorporated herein by reference.

TECHNICAL FIELD

The disclosed embodiments relate to devices and methods for treating alung and, in an embodiment, chronic obstructive pulmonary disease(COPD). More particularly, the present disclosure relates to devices andmethods of treating airways of lungs.

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a serious progressivelung disease which makes it harder to breath. It currently affects overfifteen million people in the United States alone and is currently aleading cause of death in the country. The overwhelming primary cause ofCOPD is inhalation of cigarette smoke, responsible for over 90% of COPDcases. The economic and social burden of the disease is both substantialand increasing.

FIG. 1 depicts a healthy set of lungs 10 in an individual. A wind pipeor trachea 12 connects the nose (not shown) and mouth (not shown) to thelungs 10. As air flows in through the nose and mouth of an individual,the trachea 12 transports the air to the lungs 10 for respiratoryfunctions. The trachea 12 divides into the left 14 and right 16 bronchusstems, which further divide into a plurality of bronchi 18, bronchioles20, and eventually, terminate in a plurality of alveoli 22. The alveoli22 are small air sacs which enable gas exchange with the individual'sblood stream. That is, they permit oxygen diffusion into the bloodstream, and receive and expel CO₂ during exhalation.

COPD includes emphysema. As shown in FIG. 2A, emphysema may becharacterized by the destruction of lung parenchyma 24, the functioningparts of the lungs 10. The parenchyma 24 includes the alveoli 22 walls,bronchioles 20, and the bronchi 18. Destruction of these tissues resultsin progressively increasing shortness of breath called dyspnea. As itworsens, emphysema turns the healthy alveoli 22, clustered like bunchesof grapes, into large, irregular pockets with gaping holes in theirinner walls, as shown in FIG. 2B. This reduces the surface area of thelungs and, in turn, the amount of oxygen that reaches an individual'sblood stream.

Destruction of the lung parenchyma may also lead to loss of elasticrecoil and tethering (i.e., ability to hold open walls of airways,including the bronchioles 20, leading to the alveoli 22 throughout muchof inhalation and expiration), which maintains airway patency. Unlikelarger lung airways, the bronchioles 20 are not supported by cartilageand thus have little intrinsic support. As a result, the bronchioles 20are susceptible to collapse or reduction in diameter when destruction oftethering occurs, particularly during exhalation. The collapse ofairways may prevent air in the alveoli 22 from escaping duringexhalation. A significantly reduced diameter airway 26 connecting to analveoli 22 is depicted in FIG. 2B. This trapped gas in the alveoli 22may lead to hypercapnia (high levels of CO₂ in the blood stream) andacidosis (lowering of pH levels), which are correlated to mortality inCOPD patients.

One existing approach to treat emphysema is performing lung volumereduction surgery, which removes or kills a portion of a diseased lungto allow greater expansion of remaining lung tissue. However, thisapproach poses a substantial risk due to its invasive nature. It may,therefore, be beneficial to provide a less-invasive technique fortreating emphysema, or other lung conditions including asthma.

SUMMARY

The disclosed embodiments relate to devices and methods for manipulatinglung airways in a patient for treating, for example, chronic obstructionpulmonary diseases. In one exemplary embodiment, a method of treating alung is disclosed. The method may include deploying a catheter into anairway of the lung, and discharging a media into the airway through thecatheter. The media may be configured to increase elasticity of lungtissue in the vicinity of the airway.

The disclosed method may include one or more of the following features.Discharging the media may include chemically washing the airway usingthe media; the injectable media may be one of (i) a polymer, (ii) anoil, (iii) a gel, (iv) a surfactant; discharging the media may includeinjecting the media into the airway using a needle fluidly coupled to adistal end of the catheter; and discharging the media may includeinjecting the media into a tissue of the airway.

In another exemplary embodiment, a method of treating a lung isdisclosed. The method may include deploying a catheter into an airway ofthe lung, and discharging a media into the airway through the catheter.The media may be configured to expand in the airway and occlude theairway after being discharged from the catheter.

The disclosed method may include one or more of the following features.The method may include a plurality of the media, wherein the pluralityof media may interlock together in the airway after the discharging; andwherein the media may include a drug, and the method may includereleasing the drug into the airway from the media after the discharging.

In another exemplary embodiment, a device for treating an airway of alung is disclosed. The device may include an injectable media configuredfor deployment into an airway of the lung. The media may be configuredto expand in the airway and occlude the airway. The device may alsoinclude a catheter configured for insertion into or proximate theairway. The catheter may be configured to discharge the media into theairway.

The disclosed device may include one or more of the following features.A surface of the media may include features configured to interlock witheach other; the media may include one of fibers, particles, or beads,and an average particle size of the media may be less than 300 microns;and the media may be drug-eluting.

In another exemplary embodiment, a method of treating a lung isdisclosed. The method may include deploying a catheter into an airway ofthe lung, and depositing a pattern of a media into the airway throughthe catheter. The pattern may be helicoidal. The media may include adrug suspension in a biodegradable polymer.

The disclosed method may include one or more of the following features.Depositing a helicoidal pattern may include discharging the media fromthe catheter while the catheter is rotated and translated; thebiodegradable polymer may include a low glass transition temperature;depositing a pattern may include discharging the media into the airwayin a fluid form, and solidifying the media in the airway; dischargingthe media may include heating the media above a glass transitiontemperature of the polymer, and solidifying the media may includecooling the media below the glass transition temperature; and the drugmay include a corticosteroid or a glucosteroid.

In another exemplary embodiment, a device for treating a lung isdisclosed. The device may include an injectable media. The injectablemedia may be a drug suspension in a biodegradable polymer. The devicemay also include a catheter configured to deposit a pattern of theinjectable media in an airway of the lung.

The disclosed device may include one or more of the following features.The catheter may include a substantially L-shaped tip; the catheter mayinclude a heating element or an energy transfer element (for example, aheater) configured to maintain the injectable media in a liquid state;the device may also include a rotating mechanism configured to rotatethe catheter as the injectable media is discharged into the airway.

The above summary of exemplary embodiments is not intended to describeeach disclosed embodiment or every implementation of the presentdisclosure. The figures and the description, which follow, moreparticularly exemplify these embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings illustrate the design and utility of exemplary embodimentsof the present disclosure, in which similar elements are referred to bycommon reference numerals. In order to better appreciate how theabove-disclosed and other advantages and objects of the presentdisclosure are obtained, a more detailed description of the presentembodiments will be rendered by reference to the accompanying drawings.Understanding that these drawings depict only exemplary embodiments ofthe disclosure and are not therefore to be considered limiting in scope,the disclosure will be described and explained with additionalspecificity and detail through the use of the accompanying drawings inwhich:

FIG. 1 illustrates the anatomy of healthy lungs of an individual;

FIG. 2A illustrates a lung suffering from emphysema;

FIG. 2B is a diagrammatic illustration of an airway connected to analveoli in the lung of FIG. 2A;

FIG. 3 illustrates an exemplary embodiment of a device for deploying anexemplary media in an airway of the lung of FIG. 2A;

FIGS. 4A and 4B illustrate exemplary embodiments of the distal ends of adevice configured to deploy media in an airway of the lung of FIG. 2A;

FIG. 5 illustrates the proximal end of an exemplary embodiment of adevice for deploying media in an airway of the lung of FIG. 2A;

FIG. 6 illustrates another exemplary embodiment of a device fordeploying an exemplary media in an airway of the lung of FIG. 2A;

FIG. 7A illustrates another exemplary embodiment of a device fordeploying an exemplary media in an airway of the lung of FIG. 2A;

FIG. 7B is a diagrammatic illustration of an exemplary media that may bedeployed in an airway of the lung of FIG. 2A; and

FIG. 8 illustrates another exemplary embodiment of the distal end of adevice for deploying an exemplary media in an airway of the lung of FIG.2A.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

The present disclosure is drawn to devices and methods for the treatmentof diseased tissue. Such diseased tissue may suffer from COPD and/orother lung conditions, such as asthma. Exemplary embodiments are drawnto devices and methods for the treatment of diseased tissue in thelungs. In some embodiments, the treatment may include repairing orrejuvenating the diseased tissue to improve overall lung function. Inother embodiments, the treatment may include occluding (or blocking) oneor more airways of the lungs to prevent inhaled air from reachingdiseased tissue. As inhaled air is no longer directed to the diseasedtissue, the remaining healthy tissues receive more air, and lungfunction improves. While the principles of the present disclosure aredescribed with reference to treatments for the lungs of a patient, itshould be understood that the disclosure is not limited thereto. Rather,the devices and methods may find applicability for the treatment of anyluminal tissue structure.

FIG. 3 depicts a lung airway 28 including an exemplary embodiment of adevice therein. In this disclosure, the term “airway” is used to referto any of bronchi 18, bronchioles 20, and alveoli 22. Airway 28 mayinclude diseased tissue, or may be positioned adjacent to diseasedtissue. A user (such as, a physician, etc.) may introduce an introducersheath 30 through the patient's airway 28 until a distal end of thesheath 30 reaches a target tissue area within airway 28. Sheath 30 maybe introduced into the airway 28 via any appropriate method. In anexemplary embodiment, sheath 30 is inserted into the patient through themouth (or another opening) and advanced into the airway 28. The sheath30 may be sized to access the airway (i.e. bronchi 18, bronchioles 20,or alveoli 22) that is desired to be treated. In some embodiments, oneor more light sources (fiber optic cables, light-emitting diodes, etc.)and/or image sensors may be provided on, or associated with, the sheath30 to assist the user in navigating the sheath 30 through tortuousairways 28 in the patient's body. In some embodiments, the sheath 30 mayalso include one or more radiopaque markers 52 to assist the user indetermining the proper location of the sheath 30 within the airway 28.As is known in the art, radiopaque markers 52 are indicators that areplaced at strategic locations on a catheter for visibility under x-rayfluoroscopy or radiography. The sheath 30 may be introduced into theairway 28 directly, or may be introduced through a lumen of anotherdevice, such as, for example, a bronchoscope, endoscope, etc. Whilesheath 30 is referred to and described herein, it is to be understoodthat any luminal delivery device may be used without departing from thescope of the disclosure.

In some embodiments, the sheath 30 may include a retention member suchas, for example, balloon 32, configured to transition between anuninflated (or deflated) configuration (not shown), and an inflatedconfiguration (as shown in FIG. 3). Balloon 32 may expand within theairway 28 to position the sheath 30 within the airway 28. Accordingly,the balloon 32 may be configured to receive a source of inflation fluidthrough an inflation channel (not shown) in sheath 30. In someembodiments, the sheath 30 may include means to remove air from theballoon 32 distal to the balloon 32. The sheath 30 may be introducedinto the airway 28 while the balloon 32 is in the uninflatedconfiguration (not shown). Upon reaching the desired treatment area, theballoon 32 may be inflated. Alternatively, any suitable expandablemember may be employed such as, for example, mechanical expansion cages,expandable foam members, hook and/or finger members, and expandingmembers activated by body heat or chemistry. In some embodiments, theballoon 32 (or any alternative expanding member) may include agents ordrugs (such as, for example, antimicrobial agents, analgesics, andanesthetics, etc.) to treat the airway tissue it contacts.

An exemplary medical tool may be introduced into the airway 28 throughthe sheath 30. In some embodiments, the medical tool may include asteerable catheter 40. The catheter 40 may extend from a proximal end44, positioned external to the airway 28, to a distal end 46 thatextends out of the sheath 30. The distal end 46 of the catheter 40 maybe positioned proximate the desired treatment site (for example,diseased tissue) in the airway 28. The catheter 40 may also include oneor more radiopaque markers 52 to assist in suitably positioning thecatheter 40 in the airway 28. The catheter 40 may be configured todirect an injectable media 48 into the airway 28 through its distal end46. The proximal end 44 of the catheter 40 may include one or moresteering dials (or other mechanisms) configured to articulate (or turn)the distal end 46 of the catheter 40 in different directions. Thissteering capability enables the catheter 40 to release the media 48 inany desired direction (for example, towards a bronchiole 20 leading todiseased alveoli 22 (see FIG. 1)).

The distal end 46 of the catheter 40 may include one or more orifice(s)50 adapted to discharge the media 48 into the airway 28. In general, theorifice(s) 50 may be of any size and shape, and arranged in any pattern.In some embodiments, as illustrated in FIG. 3, the distal-most tip ofthe catheter 40 may be open to form a single orifice 50. Although thecatheter 40 is described as being introduced into the airway 28 throughthe sheath 30, this is not a requirement. In some embodiments, thesheath 30 may be eliminated and the catheter 40 may be introduced intothe airway 28 directly, or via a luminal delivery device, such as abronchoscope. In some embodiments, the catheter 40 may also include aretention member (such as, balloon 32 of sheath 30) to maintain theposition of catheter 40 within the airway 28.

FIGS. 4A-4B illustrate other exemplary embodiments of a catheter thatmay be introduced into the airway 28 to discharge media 48. Asillustrated in FIG. 4A, in some embodiments, a catheter 140 may includea plurality of orifices 50 arranged around its distal end 46. Theseorifices 50 may enable the injectable media 48 to be substantiallyevenly disbursed around the distal end 46 of the catheter 140. Althoughillustrated as being substantially rectangular, these orifices 50 mayhave any shape. In some embodiments, as illustrated in FIG. 4B, thedistal end 46 of a catheter 240 may include a needle 54. The needle 54may include one or more orfice(s) 50 at, or around, its tip, and may beconfigured to inject the media 48 into, or on, a desired region of thedamaged tissue in the airway 28. In some embodiments, the needle 54 maybe configured to penetrate tissue surrounding the airway 28, anddischarge the injectable media 48 into the tissue and/or the musclesurrounding the tissue.

The injectable media 48 may be delivered to the distal end 46 of thecatheter (40, 140, 240) from its proximal end 44. FIG. 5 illustrates oneembodiment of a catheter 40 with an injector 58 containing the media 48.In some embodiments, the injector 58 may include an energy transferelement (for example, a heater) to maintain the media 48 in a heatedstate. Depressing a plunger of the injector 58 directs the media 48towards the distal end 46 of the catheter 40. In use, the distal end 46of the catheter 40 may be inserted into a patient and advanced to adesired airway 28 site. Radiopaque markers 52 (see FIG. 3) on thecatheter 40 may assist in the positioning of the catheter 40 at thedesired site. When the catheter 40 is suitably positioned, the user maydepress the plunger of the injector 58 to discharge a desired quantityof the media 48 through the orifice(s) 50 at the distal end 46 of thecatheter 40. The catheter 40 may now be moved to another location todischarge the media 48 at the new location. After all the desiredlocations have been treated, the catheter 40 may be withdrawn from thebody.

Media 48 may be discharged into the airway 28 continuously or inbatches. That is, in some embodiments, the catheter 40 may deliver afirst batch of media 48 at a first time and a second batch at a secondtime after the first time. Each batch may include any suitable amount(number, volume, etc.) of media 48. In some embodiments, a pressurizedfluid may assist in pushing the media 48 out of the catheter 40. In suchembodiments, the media 48 may be released into the airway 28 along withthe pressurized fluid. In such embodiments, the catheter 40 may becoupled to a pressurized fluid source (not shown).

In addition to, or in place of injector 58, in some embodiments, theproximal end 44 of the catheter 40 may be fluidly coupled to a pump thatis programmed to discharge a desired quantity of the media 48 throughthe catheter 40. For instance, the user may activate the pump todischarge a desired quantity of the media at the desired site. AlthoughFIG. 5 illustrates the catheter 40 as being directly inserted into thepatient, as explained previously, the catheter 40 may also be introducedinto the patient through a sheath 30 or another luminal delivery device.Further, although FIG. 5 illustrates the catheter 40 inserted into themouth of a patient, this is not a requirement. In general, the catheter40 may be inserted into the patient through any cavity that suits themedical procedure the device is applied to.

FIG. 6 illustrates another exemplary embodiment of a catheter 340 thatmay be used to deliver a desired pattern of an injectable media 48 on anairway wall (tissue surrounding the airway 28). The distal end 46 of thecatheter 340 may include a flexible substantially L-shaped tip 56 withone or more orifice(s) 50 positioned thereon. The tip 56 may beconfigured to press against, or be positioned proximate to (i.e.appose), the airway wall at a desired site. In some embodiments, a tip56 having a substantially L-shape may be attached to the distal end 46of catheter 340, while in other embodiments, the distal end 46 ofcatheter 340 may be bent to form a substantially L-shape after thecatheter 340 is suitably positioned in an airway 28. In use, catheter340 may be inserted into a patient and advanced to the desired site inthe airway 28. The substantially L-shaped tip 56 may then be positionedapposed to the airway wall and the media 48 discharged through theorifice 50. In embodiments where the shape of the tip 56 is formed byflexing the distal end 46 of the catheter 340, the distal end 46 of thecatheter 340 may be bent to position the orifice 50 proximate the airwaywall before the media 48 is discharged.

To form a desired pattern of the media on the airway wall at the desiredsite, the catheter 340 (and tip 56) may be moved as the media 48 isreleased. For instance, to deposit the media 48 along a straight line,the catheter 340 may be advanced into, or retracted from, the airway 28as the media 48 is released. To deposit the media 48 as an annular ringon the airway wall, the catheter 340 may be rotated as the media 48 isdischarged. In some embodiments, the catheter 340 may be rotated andtranslated (advanced and/or retracted) as the media 48 is beingdischarged. In such embodiments, the discharged media 48 may form ahelicoidal coating or pattern on the airway wall. In some embodiments,the catheter 340 may be moved (rotation, translation, etc.) manually bythe user as the media 48 is released. In other embodiments, a mechanismmay assist in moving the catheter 340 as the media 48 is discharged. Anysuitable mechanism may be used to move the catheter 340. In someembodiments, as illustrated in FIG. 6, the proximal end 44 of thecatheter 340 may be coupled to a rotating mechanism 60 that rotates andtranslates (advances or retracts) the catheter 340 as the injector 58 isoperated. In the exemplary embodiment of the rotating mechanism 60illustrated in FIG. 6, depressing the plunger of the injector 58 mayrotate threaded shafts, and blocks that turn on these shafts, totranslate and rotate the tip 56 as the media 48 is released.

Any suitable injectable media 48 may be delivered to the airway 28 usingthe catheter (40, 140, 240, 340). In some embodiments, media 48 may be adrug suspension mixed with a biodegradable polymer having a low glasstransition temperature (T_(g)), such as for example about 45° C. In anexemplary embodiment, media 48 (in the form of a drug suspension in abiodegradable polymer) may be heated and maintained in a semi-fluid (orgel) state in the injector 58 of FIG. 6. The catheter 40 may theninserted into the patient and advanced to the desired treatment site. Atthe treatment site, the tip 56 may be positioned proximate the airwaywall, and the media 48 released as the catheter is rotated and retracted(or advanced). The combined rotation and translation of the tip 56 maydeposit the media 48 in a helicoidal pattern on the airway wall. As themedia 48 cools below its T_(g) (for example, below about 45° C.) itsolidifies on the airway wall. The catheter 40 may then be moved todeposit a helicoidal pattern of the media 48 on other desired treatmentsites.

Any drug, without limitation, may be mixed with the biodegradablepolymer to form the media 48. In some embodiments, the drug may includelong acting corticosteroids, glucocorticoids, long actingbeta2-adrenergic (LABA) receptor argonists, and combinations thereof.Exemplary drugs that may be present in some embodiments of media 48 mayinclude hydrocortisones (such as, for example, hydrocortisone,hydrocortisone acetate, cortisone acetate, tixocortol pivalate,prednisolone, methylprednisolone, and prednisone), acetonides (such as,for example, triamcinolone acetonide, triamcinolone alcohol, mometasone,amcinonide, budesonide, desonide, flucocinonide, fluocinolone acetonide,and halcinonide), betamethasones (such as, for example, betamethasone,betamethasone sodium phosphate, dexamethasone, dexamethasone sodiumphosphate, and fluocortolone), halogenated drugs (such as, for example,hydrocortisone-17-valerate, aclometasone dipropionate, betamethasonevalerate, betamethasone dipropionate, prednicarbate,clobetasone-17-butyrate, clobetasol-17-propionate, fluocortolonecaproate, fluocortolone pivalate, and flupredenidene acetate), labileproducing esters (such as, for example, hydrocortisone-17-butyrate,17-aceponate, 17-buteprate, and prednicarbate), steroids (such as, forexample, flunisolide, fluticasone propionate, triamcinolone acetonide,beclomethasone dipropionate, budesonide), and other drugs (such as, forexample ciclesonide, salmeterol, formoterol, bambuterol, clenbuterol,etc.).

Depositing a helicoidal pattern of media 48 on airway walls may haveadvantages. The tissue of the airway walls is composed ofmucus-producing goblet cells and a ciliated epithelium (cells with hairlike protrusions or cilia protruding into the airway 28). The ciliacontinually flex (or beat) and push mucus up and out of the airway 28into the throat. This upward movement of mucus on the airway walls,called the mucociliary escalator, is a major barrier against infection.Microorganisms that enter the respiratory tract are caught in the stickymucus and moved up by the mucociliary escalator. When the solidifiedmedia 48 in the airway wall contacts the mucus, the solidified polymerundergoes hydrolysis and releases the drugs mixed in the polymer.Depositing a helicoidal pattern of the media 48 on the airway wall mayprovide the required treatment for the wall tissue without blocking themucociliary escalator.

In some embodiments, the injectable media 48 may be a pulmonarysurfactant. Pulmonary surfactant is a compound that is naturallyproduced in the lungs, and is critical for proper respiratory function.Surfactants are a complex mixture of phospholipids and proteins.Surfactant reduces surface tension in the lung (which is necessary toprevent the collapse of the alveoli and other airways 28) and reducesthe effort needed to expand the lungs during inhalation. The absence ofsufficient surfactant leads to collapse of airways 28 and compromisedpulmonary function. Exogenous replacement surfactants possess theproperties needed to lower the surface tension in the lungs. In someembodiments of the current disclosure, a surfactant may be injectedinto, or on, airway 28 tissue to rejuvenate diseased tissue in theairway 28. The injected surfactant may help the airway 28 maintain itsshape and reduce surface tension, and improve (or restore) itselasticity. Improving the elasticity of the airway may enable the airwayto elastically recoil during exhalation.

In some embodiments, the injectable media 48 may include air or anotherfluid. In such embodiments, air or another fluid may be injected on anairway 28 (such as the alveoli 22) to chemically wash the airway 28.This chemical washing may smooth muscle tone of the tissue in theairway, and restore at least some elasticity of the tissue. Improvingthe elasticity of the diseased tissue may restore some function to theairway 28. It is also contemplated that, in some embodiments, a drug ora chemical may be injected into the airway 28 to flush and therebyunclog an airway 28. Any chemical suitable for unclogging the airway 28may be injected into the airway 28 for this purpose. Although the airand the chemicals may be discharged into the airway 28 by using any ofthe devices discussed with reference to FIGS. 3-6, in some embodiments,a catheter 40 with a distal needle 54 (see FIG. 4B) may be used for thispurpose.

In some embodiments, the injectable media 48 may be a polymer, an oil,or a gel. In such embodiments, the injectable media 48 may be dischargedproximate diseased tissue in the airway 28, or injected (for example, byusing needle 54 of FIG. 4B) into the diseased tissue. Exemplary polymersmay include synthetic viscoelastic urethane polymers such as, forexample, Sorbothane®, and exemplary gels may include hydrocolloids suchas, for example, Alginate. The injected material may improve theelasticity of the tissue. In some embodiments, air may be dischargedinto the airway 28 (such as alveoli 22) to expand the airway 28 prior todischarge of the polymeric media 48. The air and the media 48 may bedelivered to the airway 28 using the same catheter 40 or by differentcatheters. For instance, in embodiments where catheter 40 is introducedinto the airway 28 through a luminal delivery device, the air may bedirected into the airway 28 through a lumen of the device and the media48 may be discharged through the catheter 40. The air may inflate acollapsed (or decreased diameter) airway 28 and allow the polymer tocoat the walls of the inflated airway 28. As the polymer cures, itselasticity increases. This increased elasticity may rejuvenate, andimprove at least to some extent, elastic recoil of the airway 28 duringinhalation and exhalation.

In some embodiments, media 48 in the form of a polymer, oil, or gel mayalso be used to necrose diseased tissue in an airway 28. For instance,an increased amount of the media 48 may be delivered to an airway 28(such as a bronchi 18 or bronchioles 20) to occlude the airway 28 andcause diseased airway tissue (for example, in an associated alveoli 22)to necrose. By removing poorly functioning tissue, the remaining lungtissue may work more efficiently and improve overall pulmonary function.

In some embodiments, as illustrated in FIG. 7A, the media 48 may includea filler or occlusive material. The filler may include any type offibers, particles, and/or beads having regular or irregular nestingshapes. In general, the fillers may have any suitable size and shape. Insome embodiments, the size of the fillers may be less than about 300microns. In some embodiments, the dimensions of the filler may beselected such that upon deployment in the airway 28, the media 48 blocks(i.e. occlude) the airway 28. In some embodiments, the shape of media 48may be such that upon deployment in the airway 28, a plurality of media48 interlock and span the airway 28 to collectively occlude the airway28. The media 48 may have any suitable three dimensional shapeincluding, but not limited to, cubical, triangular, cylindrical, andirregular shapes. In some embodiments, the media 48 may be drug-eluting.That is, the media may include a drug or a chemical that assists in thetreatment of the tissue. This drug may promote rejuvenation of thetissue (for example, similar to the drugs discussed above) or maypromote necrosis of the tissue (for example, ethanol or another embolicmaterial). It is also contemplated that, in some embodiments, the drugalone may be injected into, or proximate, the tissue at the target siteto treat the tissue.

In some embodiments, the fillers (media 48) may be configured to expand(such as, for example, radially outward) or swell when deployed in theairway 28 (for example, when the fillers come into contact with humidityin the airway 28). In such embodiments, a relatively small-sized fillerdischarged at a site (for example, a bronchiole 20) may traveldownstream and gradually expand to fill an airway 28 (for example, analveoli 22) downstream of the discharge site. In some embodiments, themedia 48 may include expandable microspheres comprising a thermoplasticshell encapsulating a low boiling point liquid hydrocarbon. When thetemperature of the microsphere reaches a threshold value, thethermoplastic shell softens. The increasing pressure of the hydrocarbonwithin the microsphere will then cause the microsphere to expand involume. In some embodiments, the microsphere dissolves to expose aconstrained (unexpanded) state of another material. This material mayexpand then expand to fill the airway 28. In some embodiments, asillustrated in FIG. 7B, the fillers (expandable or non-expandable media48) may include surface modifications (such as, for example, velcroloops, barbs 72, or other locking features) that assist in interlockingthe fillers together. Alternatively or additionally, these surfacemodifications may act as anchors to prevent the fillers from separatingfrom tissue after it is implanted. It is contemplated that, in someembodiments, the barbs 72 form on the surface of the filler only afterthe fillers are deployed in an airway 28. For instance, when the fillerscome into contact with humidity in the airway 28, the barbs 72 extend(or disentangle) from the surface of the fillers. In some embodiments, asticky surface coating on media 48 may serve as an anchor.

Any of the devices discussed with reference to FIGS. 3-6 may be used todeliver the media 48 discussed in the previous paragraphs to a desiredtreatment site at an airway 28. In an exemplary embodiment, a catheter40 may be advanced through a natural opening of the body (e.g., via amouth or nose) into the airway 28 proximate the treatment site.Radiopaque markers 52 on the catheter 40 may assist in positioning thecatheter 40 at the desired site. Once suitably positioned, a balloon 32may optionally be inflated to contact the interior walls of the airway28 and seal the airway 28 to prevent the media 48 from travelling intoadjacent regions of the lung not intended to be treated during theprocedure. In some embodiments, the media 48 may be discharged in astream of pressurized fluid (e.g., air) to achieve better penetrationdepth into the airway 28. Once a desired amount of the media 48 isdischarged at the treatment site (continuously or in batches), thecatheter 40 may be moved to a different airway 28 (or a differentportion of the same airway 28) for treatment. After all the desiredsites are treated, the catheter 40 may be retracted out of the airway.

In some embodiments, an entire portion of an airway may be occludedusing media 48. In other embodiments, only a discrete portion of theairway 28 may be occluded. In such embodiments, a space in front of theoccluded portion (or beside the occluded portion) may be left open. Insome embodiments, instead of occluding an entire area, the media 48 maybe used to reduce a cross-sectional area of an airway 28. In someembodiments, air in an airway 28 may be removed prior to being occludedby injecting media 48.

In some embodiments, instead of directly discharging the media 48 intoan airway 28, an occluder filled with a suitable media 48 may bepositioned in the airway 28 to occlude the airway 28. FIG. 8 illustratesan embodiment in which an occluder, in the form of balloon 62 filledwith media 48, is used to occlude the airway 28. In use, a sheath 130may be introduced into, and suitably positioned at, a desired treatmentsite in an airway 28. A balloon 62 (in an uninflated or deflated state)may then be delivered to the treatment site through the sheath 130. Acatheter 40, introduced to the treatment site through the sheath 130,may then be used to fill the balloon 62 with media 48 and inflate theballoon 62. The inflated balloon 62 may wedge or lock into position onthe airway walls and occlude the airway. Any of the previously discussedtypes of media 48 may be used to fill the balloon 62. In someembodiments, a thermal transition gel may be used as the media 48. Insuch embodiments, gel in a fluid state may be injected into the balloon62 to inflate it. Upon cooling, the gel may harden and press the balloon62 against the airway walls and occlude the airway 28. In someembodiments, sheath 130 may include a detachable tether 132 to detachthe balloon 62 from the sheath 130 after filling. It is alsocontemplated that, in some embodiments, the balloon 62 may includevalves or other mechanisms to prevent the media 48 from travellingupstream of the balloon 62 during filling. In some embodiments, theexternal surface 64 of balloon 62 may be coated with a chemical thathelps the surface 64 adhere to tissue and/or assist in necrosis of thetissue.

Although the exemplary embodiments described above have been disclosedin connection with devices for manipulating lung airways, those skilledin the art will understand that the principles set out above can beapplied to any bronchial device and can be implemented in different wayswithout departing from the scope of the disclosure as defined by theclaims. In particular, constructional details, including manufacturingtechniques and materials, are well within the understanding of those ofskill in the art and have not been set out in any detail here. These andother modifications and variations are well within the scope of thepresent disclosure and can be envisioned and implemented by those ofskill in the art.

Moreover, while specific exemplary embodiments may have been illustratedand described herein, it should be appreciated that combinations of theabove embodiments are within the scope of the disclosure. Otherexemplary embodiments of the present disclosure will be apparent tothose skilled in the art from consideration of the specification andpractice of the exemplary embodiments disclosed herein. It is intendedthat the specification and examples be considered as exemplary only, anddepartures in form and detail may be made without departing from thescope and spirit of the present disclosure as defined by the followingclaims.

What is claimed is:
 1. A method of treating a lung, comprising:deploying a catheter into an airway of the lung; and discharging a mediainto the airway through the catheter, the media being configured toincrease elasticity of lung tissue in the vicinity of airway.
 2. Themethod of claim 1, wherein discharging the media includes chemicallywashing the airway using the media.
 3. The method of claim 1, whereinthe injectable media is one of (i) a polymer, (ii) an oil, (iii) a gel,(iv) a surfactant.
 4. The method of claim 1, wherein discharging themedia includes injecting the media into the airway using a needlefluidly coupled to a distal end of the catheter.
 5. The method of claim1, wherein discharging the media includes injecting the media into atissue of the airway.
 6. A method of treating a lung, comprising:deploying a catheter into an airway of the lung; and discharging a mediainto the airway through the catheter, the media being configured toexpand in the airway and occlude the airway after being discharged fromthe catheter.
 7. The method of claim 6, further including a plurality ofthe media, wherein the plurality of media interlock together in theairway after the discharging.
 8. The method of claim 6, wherein themedia includes a drug, and the method further includes releasing thedrug into the airway from the media after the discharging.
 9. A methodof treating a lung, comprising: deploying a catheter into an airway ofthe lung; and depositing a predetermined pattern of a media into theairway through the catheter, the media being drug suspension in abiodegradable polymer.
 10. The method of claim 9, wherein depositing apredetermined pattern includes depositing a helicoidal pattern, andwherein depositing the helicoidal pattern includes discharging the mediafrom the catheter while the catheter is rotated and translated.
 11. Themethod of claim 9, wherein the biodegradable polymer includes a lowglass transition temperature.
 12. The method of claim 9, whereindepositing a helicoidal pattern includes discharging the media into theairway in a fluid form, and solidifying the media in the airway.
 13. Themethod of claim 12, wherein discharging the media includes heating themedia above a glass transition temperature of the polymer, andsolidifying the media includes cooling the media below the glasstransition temperature.
 14. The method of claim 9, wherein the drugincludes a corticosteroid or a glucosteroid.